The Primary Primer: A Marquee Match-Up Featuring an Obama Cousin

We have three days of primaries this week with six states voting, but today we'll be watching Kansas, Missouri, Washington, and Michigan. There's a marquee match-up in Kansas that's another GOP establishment vs. tea party brawl, and this week marks the last two possibilities the tea party could knock off an incumbent senator. They've had some victories including knocking off Eric Cantor, but they've poured loads of money into trying to topple an incumbent senator and have completely struck out in places like Kentucky, Mississippi, and South Carolina. This week will mark their last two opportunities, the first being this evening in Kansas and it even feature's a relative of the president's.

WHO'S ON THE BALLOT?

Three-term incumbent Sen. Pat Roberts is facing off against tea partier Dr. Milton Wolf, a distant cousin of President Obama in Kansas. As mentioned above this is the race to watch today, but it's not the only one with a famous Democratic family trying to continue their legacy, a former reindeer farmer who may get toppled, and even some party switchers.

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Here are seven races to watch tonight:

KANSAS' MARQUEE MATCH-UP: Sen. Pat Roberts is another incumbent fighting the tea party insurgency as his opponent, radiologist Milton Wolf, comes in swinging from the right in Kansas' Senate GOP primary. Wolf-who has never before run for public office and is related to the president on his mother's side-has been playing into the anti-Washington sentiment across the country and attacking Roberts for being in Washington for far too long. WHY IT MATTERS? Roberts, 78, served in the House from 1981 to 1997 and has served in the U.S. Senate since then. Both candidates have made serious mistakes and in Wolf's case this may have prevented him from gaining the steam other challengers have. In February it was uncovered that in 2010, the radiologist posted X-rays of grisly imagesof fatal injuries to Facebook and cracked jokes about them. Even with that mishap, Wolf has still been able to receive support from groups like the Senate Conservatives Fund, Tea Party Express, and the Madison Project. Roberts immediately jumped on the scandal by running statewide television ads highlighting the issue, as well as a state medical board investigation into Wolf's behavior. Also in February, Roberts was faced with his own controversy, when the New York Times reported he owned a home in the Washington, D.C., suburb of Alexandria, Virginia, but not in Kansas. Wolf has become a larger threat than Roberts and his campaign initially believed, but polls show it's still likely the incumbent comes out victorious tonight, despite making other flubs about his residency throughout the campaign. If there is a surprise, polls show the Democrat in the race, District Attorney of Shawnee County Chad Taylor, could have a chance against Wolf in this red state.

A COMEBACK EFFORT IN KOCH TERRITORY: Incumbent GOP Rep. Mike Pompeo faces former Congressman Todd Tiahrt, who represented the district from 1995 to 2011, in the face off for the GOP primary for Kansas' fourth district. Tiahrt retired from his seat in 2010 in an unsuccessful bid for Senate, when he lost to current Sen. Jerry Moran, and now he's trying to make a comeback. WHY IT MATTERS? This district includes Wichita where Koch Industries is based and the billionaire conservative brothers have run radio and television ads through their group Americans for Prosperity backing Pompeo over Tiahrt. They've hit Tiahrt over earmarks and wasteful spending. In an effort to carve out a lane of his own, Tiahrt has accused Pompeo of rewarding campaign donors like agricultural businesses with legislation that would prevent states from requiring labels for genetically modified foods. Pompeo's campaign has said that he introduced the legislation to help Kansas farmers, who use bio-engineered ingredients in certain foods to ward off pests and insects.

IT'S A FAMILY AFFAIR: After 80 years and two Dingells serving, Michigan's twelfth district has the opportunity to send one more to Congress. Dingell Sr. served in the House of Representatives from 1933 until his death in 1955. John Dingell Jr., the longest-serving member of Congress in history has served since 1955, and now Debbie Dingell, his wife, hopes to carry on the legacy and is widely favored to win. WHY IT MATTERS? Dingell who is in his 59 th year representing Michigan announced his retirement in February, saying he was fed up over partisan gridlock. Debbie Dingell, former president of the GM Foundation, will face Raymond Mullins in the Democratic primary, former president of the Ypsilanti-Willow Run NAACP. Dingell not only carries the upper hand in name recognition, but also in fundraising, swamping her rival. Mullins has criticized his opponent, saying she is just running on her famous last name, but she has said she is her own person, telling the Ann Arbor News, "I could never fill John Dingell's shoes…I'm not going to try to fill John Dingell's shoes. And I'm not John Dingell. I'm Debbie Dingell." It's likely the victor will be the winner in November.

TRYING TO TOPPLE A TEA PARTY DARLING: Incumbent GOP Rep. Justin Amash is facing a fellow Republican challenger with equal fundraising prowess and an endorsement from the U.S. and Michigan Chambers of Commerce, as well as other GOP establishment support, but it still looks like Amash will come out victorious in the GOP primary for Michigan's third district. Grand Rapids businessman Brian Ellis is looking to unseat Amash and has attacked his voting record in the House as not being in line with the citizens he represents. WHY IT MATTERS? Establishment Republicans are looking to Ellis to unseat a congressman who they feel does not always align with the party, but taking down Amash is no easy feat. He has the backing of the Koch-backed Americans for Prosperity as well as the Club for Growth, and the tea party group FreedomWorks. The most eye-popping moment of the campaign was an ad Ellis ran characterizing Amash as "Al Qaeda's best friend," quoting Rep. Devin Nunes, R-California, who made the comment in an interview with Politico in May. Polls show Amash with a wide lead so it's likely despite the establishment effort, Amash will hang on to irritate them. Voters in this Western Michigan district consistently vote Republican, so the winner of this race is likely be the November victor as well.

THE ACCIDENTAL CONGRESSMAN: Incumbent GOP Rep. Kerry Bentivolio was propelled into the U.S. House of Representatives in 2012 after former Rep. Thaddeus McCotter was disqualified for having forged signatures on his campaign petition and ultimately resigned his seat. Bentivolio, who had widely been considered a longshot to win the Republican primary, was the only other option on the ticket until a short time before the election when a state senator waged an unsuccessful write-in campaign. Bentivolio, a former reindeer farmer and Santa Claus impersonator, ultimately won the primary which, in the conservative district led to victory in the general election as well, landing him a seat in Congress. But, now Bentivolio has a serious opponent in foreclosure attorney David Trott in the GOP primary for Michigan's eleventh district. WHY IT MATTERS? Trott, a multimillionaire known as the "foreclosure king," has been leading Bentivolio in polling and has both outspent and advertised far more heavily. Trott has establishment backing, earning the support of the U.S. Chamber of Commerce, as well as Michigan native Mitt Romney.

THE OTHERS:

DEMOCRATIC PRIMARY FOR MISSOURI'S FIFTH DISTRICT: Five of Missouri's eight members of Congress have primary challengers, but their opponents all have less campaign cash and name identification. This race is the most notable, not because Democratic incumbent Rep. Emanuel Cleaver necessarily faces any huge threat today in this Kansas City district, but because he has four challengers, including two who previously ran as Republicans in 2012, Mark Memoly and Bob Gough. Memoly ran in the 2012 GOP primary for U.S. Senate, losing against the much-talked-about Todd Akin. Gough ran for the GOP nomination for the sixth district, also losing. Gough is running against the Affordable Care Act, as is Eric Holmes, a first time politician. Charles Lindsey has the lowest visibility in the race, but ran for the same seat in 2000.

WASHINGTON STATE'S FOURTH DISTRICT: Twelve candidates are gunning to replace Republican Rep. Doc Hastings, who is retiring after nearly 20 years in Congress. The crowded 12-candidate field of contenders includes eight Republicans, two Democrats, and two independents. Washington State, like California, uses a "jungle" primary system which means the top two candidates receiving the most votes, regardless of party affiliation, will make it on to the general election ballot in November. Four of the Republicans running, former NFL tight-end Clint Didier, state Sen. Janéa Holmquist, former state Agriculture Director Dan Newhouse, and healthcare attorney George Cicotte seem to be the most serious contenders. Democratic candidate and former congressional staffer Estakio Beltran, who landed a spot on our 2014 Campaign Ad Hall of Fame, is hoping to make it to the top of the heap, but he's also handy with a shotgun.